Designed 50 odd years ago, the electrical system on the 31’ Commander Sports Express never anticipated the amount of electronic accessories nor the newer safety standards that are the norm today. Little by little I have worked to eliminate rat’s nests of added on DC wiring and in-line fuses in forgotten locations as well as upgrade the AC panel. I recently finished off this long running project.
The original 30 Amp panel box with its two screw-in plug fuses was replaced long ago with pretty much the same type of household “Square D” box but with circuit breakers instead of fuses. The original wiring from the shore power plug in the cockpit to the panel box was replaced with household 3 conductor solid copper wire. Not at all up to current marine electrical code. But except for the wire, it was essentially the same as the original equipment and no animals were harmed during years of product testing.
Old AC box, only pic I could find.
Recently, I decided to go all 21st century with a new Blue Sea Systems 30 amp panel (Model 8412) with 6 positions (circuits). That solid core 14 ga. household wire was replaced with stranded marine type 3 conductor insulated wire. I made an enclosure for the new panel out of scrap mahogany.
On the 31’ SE, the AC panel is mounted just under the starboard side of the hatch opening in the cabin floor. Essentially, it’s in the bilge. I suspect there is some sort of code rule about this. But that’s where it was and there was really nowhere else to put it. I did pick a horizontal type panel to keep it as high as possible and it is mounted in a fairly secure enclosure. The location was moved to the forward edge of the hatch opening to facilitate crawling around down there to service the front end of the 427s (too tight in the engine compartment to access the water pump and oil filter). I moved the original engraved tag to the new location as a nod to originality.
The DC “panel” on the 31’ SE is really just a recessed area on the wall in the hanging locker directly forward of the helm with drilled holes for round AGC fuse holders and identification plates for each circuit. One “Extra” fuse was provided for adding on. Generally, there is room for more. You could re-engineer with a new, modern panel. But I like to keep things original whenever possible.
Back side of DC panel under helm.
I needed a couple of more new fuses than I had space for so I enlarged the opening at the bottom. Attaching a few strips of wood to act as a guide, I used a palm sized router and a ½” deep x 3/8” diameter top guided mortising bit. Unfortunately, the bit broke off with just 1” to go. So I had to use a small chisel to finish the cut. If you do this, take it slow as the bit heats up and with the small diameter shank, it will break if stressed too much. The piece I cut out was not glued to the plywood panel behind it so it just lifted out.
Template for router
Completed cut out. Chisel used in top right corner to finish the cut.
AGC type panel mount fuse holders all seem to all look alike. But there are actually several different types and variances from brand to brand. “Bussman HKP-HH high profile AGC 15 amp panel mount fuse holders” are the exact match to the originals. They are available from many sources but prices vary quite a bit. I got mine on-line from Jameco Electronics for the low price of $1.95 each. Two day shipping was about $8. I taped the new plastic plates together, held the group in position and traced the hole in the plates to mark the position for each new fuse. Enlarge the hole a bit if necessary to get the ID plates to line up.
Buss fuse holder. High profile means taller in this area.
Adding engraved ID plates for the new fuses to match the originals was the final touch. I sourced them from Bernard Engraving for about $11 each. The tan color is a close match. The lettering is just a tiny fraction larger. If you look close you can see that some of the ID plates have mounting holes and some do not. The ones without holes are actually one solid panel with engraved dividing lines. When optional equipment was added, the ID plate had mounting holes. But they were not used. The ID plates from Bernard come ether way. I chose the plates with holes to continue this odd style quirk.
Finished with ID plates
Holes or no holes??? (Odd man out fuse holder for wipers has been replaced.)
The “Extra” fuse is once again unused. Time to find something else to power!